Rheumatoid Arthritis Health Center

Rheumatoid Arthritis: New Treatment Target?

June 30, 2009 -- Scientists have found a potential new target for rheumatoid arthritis treatment.

That target is an immune system compound called tenascin-C. In a new study, researchers report that tenascin-C is needed to sustain joint inflammation and boosts production of certain inflammatory chemicals, setting the stage for joint destruction in rheumatoid arthritis.

Most people don't have much tenascin-C in their joints, but it's present in higher levels in the joints of rheumatoid arthritis (RA) patients, note the researchers, who included Kim Midwood, PhD, of the Kennedy Institute of Rheumatology at London's Imperial College.

Midwood's team found that when mice were exposed to a certain chemical that induces an RA-like condition, mice that can't make tenascin-C for genetic reasons only had brief inflammation and still had healthy joints, while normal mice sustained persistent inflammation and joint damage.

The researchers also studied cells from people with rheumatoid arthritis. In test tube experiments, those cells ramped up their production of inflammatory chemicals when exposed to tenascin-C. That could lead to persistent inflammation and joint damage, note Midwood and colleagues.

"We hope our new findings can be used to develop new therapies that interfere with tenascin-C activation of the immune system and that these will reduce the painful inflammation that is a hallmark of this condition," Midwood says in a news release.

Midwood's study appears in the advance online edition of Nature Medicine.